Remove unnecessary #[bundle()]

Appears this just isn't needed anymore as I had removed the others
without issue.

In 0.10 `#[bundle]` was used, in 0.11 `#[bundle(ignore)]` was added,
 causing `#[bundle]` to error. I couldn't find mention of how migrate
`#[bundle]` but removing it seems to just work.

examples/press_duration.rs

@@ -38,7 +38,6 @@ pub struct Player;
 struct PlayerBundle {
     player: Player,
     velocity: Velocity,
-    #[bundle()]
     input_manager: InputManagerBundle<Action>,
     sprite: SpriteBundle,
 }